This invention relates to fuels, e.g., motor fuels for internal combustion engines and fuel oils, e.g., for oil-burning installations, in emulsion form, and containing water and emulsifiers. Furthermore, it relates to the use of an emulsifier system for the production of motor fuels and fuel oils.
It is already known that addition of water or motor fuels and fuel oils has a positive effect on the combustion process. A reduction in the amount of harmful exhaust gas components, above all nitrogen oxides and carbon black (cf. Chemical Engineering, Nov. 11, 1974, pages 84-88), is especially observed. Water has conventionally been injected via nozzles into combustion chambers. Primarily, water has been introduced directly into the motor fuel or the fuel oil. Since water is immiscible with motor fuels and fuel oils, emulsions have been formed using emulsifiers. Thus far, nonionic emulsifiers have been used exclusively for this purpose (cf. DE-OS No. 15 45 509, DE-OS No. 19 37 000=U.S. Pat. No. 3,756,794).
The water-motor fuel or water-fuel oil emulsions produced with nonionic emulsifiers where they exhibit adequate stability, are so highly viscous that below +5.degree. C. their permeability through filters and nozzles disappears. If they are set for low viscosity, then they exhibit inadequate stability, i.e., the phases separate. According to No. EP-Bl-0 012 202, the stability of motor fuel- and fuel oil-water emulsions which contain a nonionic emulsifier can be improved by special cleaning precautions. For example, the emulsifiers exhibit less than 1000 ppm of salt proportions, less than 1% by weight of polyalkylene glycol ether and less than 1% by weight of glycerol and/or polyglycerol. It is obvious that such costly cleaning operations seriously burden an industrial process.